The formation of three-dimensional shapes to create a building structural support which is formed from a plurality of individual panels is well-known. However, the formation of such large structures constructed from a single foldable sheet of material is uncommon. The field in which folded constructions are most widely used is small folded ornamental forms, traditionally using paper, which is an area pertinent to one embodiment of the present invention. Folded paper ornaments usually begin with flat, die-cut, sometimes prescored, geometric patterns to be folded into interesting shapes.
There are, however, many problems with these paper constructions. Paper ornaments generally emphasize the nature of the paper and often are folded into complicated, unstructured, somewhat flat configurations which are vulnerable to rumpling and are easily damaged. Prior art paper shapes that are folded into three-dimensional closed forms are inherently structurally weak and are vulnerable to being crushed during handling, storing or shipping. Furthermore, most three-dimensional constructions require complex-shaped blanks which dictate intricate folding and gluing methods to achieve the desired form. These are frequently offered as craft projects requiring do-it-yourself construction. Another problem is that paper ornaments or sculptured forms often reveal the edges of the construction material which-are thus more readily exposed to being torn or frayed. Therefore, folded paper forms of these constructions are generally perceived to be short-lived and are not considered high quality products that would compete with more sophisticated ornaments in the marketplace, such as glass, wood or metal.
The following U.S. Patents are the closest prior art of which the applicant is aware.
U.S. Pat. No. 4,492,723, entitled "Curvilinear Polyhedral Construction Kit", discloses a construction kit in which flat blanks may be folded into three-dimensional solid objects in which all surfaces are arcuate and clusters of polyhedrons. The methods and structures disclosed in this patent disregard ease of folding and assembly, and do not provide aesthetically pleasing shapes derived from folded engineered structure which would produce forms capable of the structural rigidity which the folded pattern of the present invention provides.
U.S. Pat. No. 3,799,425, entitled "Blank for Making Containers and Container with Top Formed by Curved Surfaces", discloses a container which can be formed from a single paperboard blank divided by fold lines. The container has a combination of single curved surfaces terminating in sharp edges and corners. The sharp edges result in a box-like container having a dome-shaped top. The top is held together by fastening together tabs which fall in the center of the top.
U.S. Pat. No. 4,712,725, entitled "Container with Integral Fold-In Closure Lid", discloses a container for dispensing foods and for storing articles which includes its own integrally-formed closure lid. The sides of the tapered cylindrical container are folded inward at the top along triangular fold lines which meet at the center to form a lid. The fold pattern does not provide a dome shape for external vertical structural integrity, but rather provides a concave top surface which facilitates a locking action to better retain articles inside the container.
U.S. Pat. No. 3,668,796, entitled "Combination Greeting Card and Three-Dimensional Ornament", discloses a greeting card that folds flat for mailing and can be folded into a three-dimensional ornament for decorative purposes. The blank from which the ornament is made is generally rectangular and none of the fold lines are arcuate. The resulting article is a polyhedron, made up of many flat sides and straight edge corners.
None of the above-described references teach or suggest the construction of the present invention which provides significant advantages. None provides a three-dimensional, folded engineered structure which is sphere-like with integrally-formed structural ribs having the aesthetically pleasing shape of the present invention.